FreeArc Portable is the fully portable version of FreeArc, which is possibly the fastest and most powerful compression tool available, free or not. FreeArc uses a variety of fast algorithms and automatic switching by file type to achieve impressive speeds, and it squeezes many file types smaller than other tools of its type. It's widely compatible with other compression software and file types. FreeArc Portable's performance is essentially identical to the installed version, but without having to be installed or uninstalled: Just delete the program file to remove FreeArc Portable from your Windows PC. It can run from a USB drive or other portable device, too.
Be sure to extract FreeArc Portable's compressed download to an easy-to-find destination since there's no installer to start the process. Everything you need to run FreeArc Portable is in the unzipped program folder, but you'll need to open the bin folder to find the executable file, which you'll click to launch the program. The user interface has just the right touches of color to break up the plain but extremely efficient layout. And FreeArc Portable is fast. While it did manage to squeeze videos (such as stored DVDs) a bit tighter than similar tools, such files are so hard to compress that the difference was negligible.
For everyday use and desktop systems, the installed version of FreeArc is the better choice since it integrates more fully with Windows. But you can, and should, have both: FreeArc as your primary compression utility, and FreeArc Portable on an external source, ready to run on another machine if and when you need it.